如何解决Angular11 Web 应用程序被 CORS 策略阻止：在预检响应中 Access-Control-Allow-Headers 不允许 access-control-allow-origin？

我正在尝试使用带有 angular 11 的 reddit api 在本地开发一个网络应用程序，我正在尝试使用以下链接中的说明获取身份验证令牌：Reddit OAuth2 docs

但是，我遇到了一些问题。

我已经设置了我的标头以包含服务中的常用方法，例如：

httpOptions = {
headers: new HttpHeaders({
  "Content-Type": "application/x-www-form-urlencoded","Access-Control-Allow-Origin": "*","Access-Control-Allow-Methods": "GET,HEAD,OPTIONS,POST,PUT","Access-Control-Allow-Headers": "Origin,X-Requested-With,Content-Type,Accept,x-client-key,x-client-token,x-client-secret,Authorization",})

};

我设置了在服务中检索身份验证令牌的函数：

getRedditAuthToken() {
 console.log("Auth token");
 return this.http.get<any>(this.redditAuthUrl,this.httpOptions);
}

redditAuthUrl 的设置参数取自 reddit 的 oAuth 文档：

https://www.reddit.com/api/v1/authorize?client_id=CLIENT_ID&response_type=TYPE&
state=RANDOM_STRING&redirect_uri=URI&duration=DURATION&scope=ScopE_STRING

最后，服务正在被组件检索：

getRedditAuthToken(): void {
    this.redditService.getRedditAuthToken().subscribe((data) => {
      console.log(data);
    });
  }

虽然在尝试访问身份验证令牌（在网络检查器上找到）时出现以下错误：

Access to XMLHttpRequest at ''https://www.reddit.com/api/v1/authorize.compact?client_id=<client_id>&response_type=code&state=<random_string>&redirect_uri=http://localhost:4200/reddit&duration=temporary&scope=identity'' from origin ''http://localhost:4200'' has been blocked by CORS policy: Request header field access-control-allow-origin is not allowed by Access-Control-Allow-Headers in preflight response
GET https://www.reddit.com/api/v1/authorize.compact?client_id=<client_id>&response_type=code&state=<random_string>&redirect_uri=http://localhost:4200/reddit&duration=temporary&scope=identity net::ERR_Failed
ERROR HttpErrorResponse {headers: HttpHeaders,status: 0,statusText: "UnkNown Error",url: "https://www.reddit.com/api/v1/authorize.compact?cl…ost:4200/reddit&duration=temporary&scope=identity",ok: false, …}

我曾多次尝试解决方案，例如使用代理 json 文件启动 angular、修改 httpHeaders、测试其他 reddit oAuth 令牌检索（使用 post 方法），但我总是遇到相同的 CORS 问题。

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

如果你已经找到好的解决方法，欢迎将解决方案带上本链接一起发送给小编。

小编邮箱:dio#foxmail.com (将#修改为@）

$http.post($rootScope.URL, {params: arguments}, {headers: {    "Access-Control-Allow-Origin" : "*",    "Access-Control-Allow-Methods" : "GET,POST,PUT,DELETE,OPTIONS",    "Access-Control-Allow-Headers": "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With"}

$http.post($rootScope.URL,{params: arguments},{headers: {
    "Access-Control-Allow-Origin" : "*","Access-Control-Allow-Methods" : "GET,POST,PUT,DELETE,OPTIONS","Access-Control-Allow-Headers": "Content-Type,Access-Control-Allow-Headers,Authorization,X-Requested-With"
}

var req = {
    method: 'POST',url: 'http://url/myPHP.PHP',headers: {
        'Authorization': 'Basic ' + btoa('username:password'),'Content-Type': 'application/x-www-form-urlencoded'
    },xhrFields: {
       withCredentials: true
    },crossDomain: true,data: xmlString
}

$http(req).then(function () {
    console.log("OK!");
});

<?PHP
    echo "You have CORS!";
?>

401 Unhauthorized
XMLHttpRequest cannot load http://url/myPHP.PHP. Response to    preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:8888' is therefore not allowed access. The response had HTTP status code 401.

setenv.add-response-header = ( "Access-Control-Allow-Origin" => "*" )

server.modules = (
    # ...
    "mod_fastcgi","mod_rewrite","mod_redirect","mod_setenv",## before mod_status
    "mod_status",# ...
)

<?PHP
header("Access-Control-Allow-Origin: *");
?>

setenv.add-response-header = ( "Access-Control-Allow-Origin" => "example.com" )
setenv.add-response-header = ( "Access-Control-Allow-Credentials" => "true" )

<!-- DWXMLSource="http://weather.yahooapis.com/forecastrss?w=38325&u=c" --><xsl:stylesheet version="1.0"xmlns:xsl="http://www.w3.org/1999/XSL/Transform"exclude-result-prefixes="yweather"xmlns:yweather="http://xml.weather.yahoo.com/ns/rss/1.0" xmlns:geo="http://www.w3.org/2003/01/geo/wgs84_pos#"><xsl:output omit-xml-declaration="yes" indent="yes"/><xsl:strip-space elements="*"/><xsl:template match="/">    <img src="{/*/*/item/yweather:condition/@text}.jpg"/></xsl:template></xsl:stylesheet>

<div id="result"><script type="text/javascript">$(''#result'').load(''weather.xsl'');</script></div>